Outline the Working Memory Model

• The working memory model replaced the idea of a unitary STM. 
• Active processing and a short term storage of information
• Name components
• Name the relationship between them

Limitations

• not much is known about the Central Executive
• evidence suggests the central executive is not unitary
• the link between working memory and LTM is not fully explained

Strengths

the working memory model explains not only the storage, but also the processing of information. Specificity. Because the model proposes specific and separate functions and subsystems, new predictions and hypotheses can be drawn up for testing. It is consistent with records of brain-damaged patients.

Evidence for visuospatial sketchpad Baddeley et al (1973) Participants were given a visual tracing task (they had to track a moving light with a pointer). At the same time they were given one of two other tasks; task 1 was to describe all the angles on the letter F, task 2 was to perform a verbal task. Task 1 was very difficult, but not task 2, presumably because the second task involved two different slave systems. This is also evidence related to the effects of doing two tasks using the same or different components.

Phonological loop It seems that the phonological loop holds the amount of information that you can say in 1.5 - 2 seconds (Baddeley et al, 1975). This makes it hard to remember a list of long words such as ‘association’ and ‘representative’ compared to shorter words like ‘harm’ and ‘twice’ and therefore stops the rehearsal of longer words! this is the word length effect

Word length effect disappears if a person is given an articulatory suppression task (asked to repeat ‘the, the, the’ while reading the words). The repetitive task fills up the articulatory process and means you can’t rehearse the shorter words more quickly than the longer ones, so the word length effect disappears. However, some words could still be recalled. Therefore it is likely the central executive takes over.

Central Executive Bunge et al (2000) used fMRI to see which parts of the brain were most active when participants were doing two tasks (reading a sentence and recalling the final word in each sentence). The same brain areas (pre-frontal cortex) were active in either dual or single task conditions but there was significantly more activation in dual task condition.

Baddeley et al (1987) PPTs were shown words and then immediate recall Recall was much better for sentences (related words) than unrelated Supports idea of ‘general’ memory store that draws on LTM (semantics)